The present invention relates to an arrangement for measuring the quantity of heat given off by a heating body to a space and for simultaneously controlling a fluid stream which passes through the heating body and serves as a heat carrier, for the purpose of regulating the space temperature.
Arrangements of the above-mentioned general type are known in the art. A known arrangement includes a volume stream regulator for allowing a constant fluid stream and an on-off valve which is precontrolled from a signal generator such as a space thermostat via control valve and switched from the energy of the fluid stream for blocking or unblocking the fluid stream as well as a temperature sensor for feed and feedback of the heating body and an electronic unit which determines the heat quantity by integration of temperature difference value converted into an electrical value during the opening times of the on-off valve. One of such arrangements is disclosed, for example, in the EP-OS No. 0018566, application Ser. No. 80 102 118.9. The known arrangement serves for controlling a fluid stream and simultaneously measuring the given off heat quantity. However, it is not accurate and expensive especially in the sense of manufacture and installation. The regulating member of the volume stream rgulator is composed of a dosing piston which slides in a cylindrical pipe. In the event of considerably dirtied heating water the sliding regulating parts can lead to errors and deviations because of corrosion and dirt deposits and finally can be clamped with one another. Also such a piston regulator requires a high working pressure because of the friction so that high pump pressures are needed. Further, the on-off valve provided with a movable valve piston can be clogged by not pure heating water, and during opening and closing of this on-off valve, leakage losses can take place so that a measuring error is produced.